The present invention relates to improvements in joint arrangements. More particularly, the invention is concerned with a dismantable joint arrangement for joining members in such a way that they are held together in a rigid and stable relationship in the assembled position, but yet can be easily disassembled for convenient shipping or storage.
In U.S. Pat. No. 3,387,868, there is described a multiple member joining arrangement for furniture and the like. The joining arrangement comprises at least three subdivided members extending toward and through one another to intersect at a common joint, each member including at least three sets of submembers, with at least two submembers in each set. Both the sets and submembers are spaced from and parallel with each other at the joint. The submembers of each member extend through the space between the sets and submembers of the other members in physical contact at the joint to provide a large contact area. Adhesive means such as glue is utilized in securing these submembers where they are in physical contact, thereby providing a high strength joint with good adhesion due to the greater adhesive area. Since adhesive is employed, it is apparent that this type of joint arrangement requires a large number of submembers in order to provide the necessary large surface area for adhesive, at the joint.
Similar joint arrangements are also disclosed in U.S. Pat. Nos. 1,066,212 and 3,779,657. In the former patent, instead of adhesive, wires are used as fastening means, which extend through overlapping or intersecting rods; since the wires are forced through bores of slightly smaller cross-section, the rods are connected to each other in such a way that they cannot be separated. In the latter patent, on the other hand, which discloses a structural joint comprising three pairs of spaced parallel beams, the beams of any one pair lying exterior to the beams of a second included pair and interior to the beams of a third pair, tension members such as threaded rods with nuts join the beams, of each pair and bias them together against the included beam pair. These tension members pass through an intersection void defined by the three pairs of beams and the members extending between the beams of each pair are in skewed relationship to those of the other pairs.
It is apparent that in both the above U.S. Pat. Nos. 1,066,212 and 3,387,868, once the joint arrangement has been assembled it cannot be dismantled, whereas in the case of U.S. Pat. No. 3,779,657 a special tool such as a wrench or a pair of pliers is needed to disengage the nuts from their respective rods in order to disassemble the joint. In this respect, it is often desirable particularly in the field of furniture to arrange frame elements and leg elements of a piece of furniture in a way such that they may be easily assembled without the need of nails, screws, adhesive or the like and/or without the use of special tools, while still presenting a rugged and sturdy article of furniture in the assembled position, and yet can be easily disassembled to provide a knocked-down structure for convenient shipping or storage.